Service tool for coupling to a service port receiver associated with a gearbox

Abstract

A service tool releasably couples to a service port receiver connected to a service port associated with a gearbox. The tool includes a coupling for releasably coupling to the service port receiver. The coupling is configured for rotational movement about the receiver between a released and engaged positions. A locking actuator couples to the coupling arrangement for axial movement between locked and unlocked positions relative to the receiver. A plunger actuator connects to the fluid conduit and is slidably coupled to the coupling arrangement for movement between open and closed positions. In the open position, with the coupling arrangement in the engaged position and the locking actuator in the locked position, the plunger actuator contacts a check valve of the service port receiver and opens it to permit fluid flow between the gearbox and the fluid conduit via a fluid pathway formed at least in part by the plunger actuator.

The invention claimed is: 
     
         1 . A service tool for coupling to a service port receiver associated with a gearbox, said tool comprising:
 a coupling arrangement adapted to releasably couple to the service port receiver, the coupling arrangement configured for rotational movement about the service port receiver between (a) a released position where the coupling arrangement is released from the service port receiver permitting axial movement of said coupling arrangement relative to said service port receiver, and (b) an engaged position where the coupling arrangement engages the service port receiver preventing axial movement of said coupling arrangement relative to said service port receiver,   a locking actuator operatively coupled to the coupling arrangement and arranged for axial movement between (i) a locked position where the locking actuator releasably engages the service port receiver preventing rotation of the coupling arrangement thereby retaining it in the engaged position, and (ii) an unlocked position where the locking actuator disengages the service port receiver permitting rotation of the coupling arrangement to the released position for its release from said service port receiver;   a plunger actuator adapted for connection to a fluid conduit, said plunger actuator being slidably coupled to the coupling arrangement for movement between an open position and a closed position where in the open position, with the coupling arrangement in the engaged position and the locking actuator in the locked position, the plunger actuator is adapted to contact a check valve of the service port receiver and open it thereby permitting fluid flow between the gearbox and the fluid conduit via a fluid pathway formed at least in part by the plunger actuator;
 the plunger actuator including a plunger member arranged for sliding movement within the coupling arrangement between the open and closed positions, the plunger member partly defining the fluid passageway; 
 the coupling arrangement including a coupling body surrounding at least part of the plunger actuator, and a key member having an operative end radially projecting inward of the coupling body for guided movement along an axially directed keyway formed in the plunger member of the plunger actuator during movement of said plunger actuator between its open and closed positions. 
   
     
     
         2 . The service tool as claimed in  claim 1  wherein the locking actuator includes an elongated locking member adapted for axial movement into and out of engagement with a corresponding cavity of the service port receiver during movement of the locking actuator between the locked and unlocked positions, respectively. 
     
     
         3 . The service tool as claimed in  claim 2  wherein the plunger member of the plunger actuator includes a circumferential groove formed continuous with the axially directed keyway and arranged with the plunger actuator in the open position for guided rotational movement of the plunger actuator within the coupling body toward a retained position preventing axial movement of the plunger actuator and thus retaining the check valve of the service port receiver in the open position. 
     
     
         4 . The service tool as claimed in  claim 3  wherein the circumferential groove extends only partly around the plunger member and includes an abutment for abutment with the operative end of the key member with the plunger actuator in the retained position whereupon the locking member of the locking actuator being engaged with the service port receiver limits further rotation of the plunger actuator relative to said service port receiver. 
     
     
         5 . The service tool as claimed in  claim 2  also comprising biasing means operatively coupled to the locking actuator for axial biasing of the locking member toward the locked position. 
     
     
         6 . The service tool as claimed in  claim 5  wherein the biasing means includes a compression spring located between the locking actuator and the plunger actuator, said spring acting against the plunger actuator which is restricted from axial movement relative to the coupling arrangement via interaction of the axially directed keyway of the plunger member of the plunger actuator and the key member of the coupling arrangement. 
     
     
         7 . The service tool as claimed in  claim 1  wherein the plunger member of the plunger actuator is a tubular member of a blind configuration including a plurality of radially-directed fluid apertures at its blind end, said apertures being exposed on opening of the check valve to permit said fluid flow via the fluid pathway. 
     
     
         8 . The service tool as claimed in  claim 1  wherein the coupling arrangement includes a coupling head having an oval-shaped opening formed partly by opposing and internally directed flanges adapted on part rotation of the coupling head about the service port receiver to interlock with a corresponding rebate on said service port receiver. 
     
     
         9 . The service tool as claimed in  claim 8  wherein the coupling head and the service port receiver are configured wherein the releasable engagement of the locking member of the locking actuator with said service port receiver occurs during the interlock of the coupling head and said service port receiver. 
     
     
         10 . In combination a service tool and service port receiver comprising:
 (1) a service port receiver adapted for connection to a service port associated with a gearbox;   (2) a service tool comprising:
 a coupling arrangement for releasable coupling with the service port receiver, said arrangement configured for rotational movement about the service port receiver between (a) a released position where the coupling arrangement is released from the service port receiver permitting axial movement of said coupling arrangement relative to said service port receiver, and (b) an engaged position where the coupling arrangement engages the service port receiver preventing axial movement of said coupling arrangement relative to said service port receiver, 
 a locking actuator operatively coupled to the coupling arrangement and arranged for axial movement between (i) a locked position where the locking actuator releasably engages the service port receiver preventing rotation of the coupling arrangement thereby retaining it in the engaged position, and (ii) an unlocked position where the locking actuator disengages the service port receiver permitting rotation of the coupling arrangement to the released position for its release from said service port receiver; 
 a plunger actuator adapted for connection to a fluid conduit, said plunger actuator being slidably coupled to the coupling arrangement for movement between an open position and a closed position where in the open position, with the coupling arrangement in the engaged position and the locking actuator in the locked position, the plunger actuator is adapted to contact a check valve of the service port receiver and open it thereby permitting fluid flow between the gearbox and the fluid conduit via a fluid pathway formed at least in part by the plunger actuator; 
 the plunger actuator including a plunger member arranged for sliding movement within the coupling arrangement between the open and closed positions, the plunger member partly defining the fluid passageway; 
 the coupling arrangement including a coupling body surrounding at least part of the plunger actuator, and a key member having an operative end radially projecting inward of the coupling body for guided movement along an axially directed keyway formed in the plunger member of the plunger actuator during movement of said plunger actuator between its open and closed positions.